1. Technical Field
The present disclosure relates to electrical transformers, and more particularly, to compact electrical transformers exhibiting a greater degree of efficiency as compared with current electrical transformers and assemblies including the same.
2. Background of Related Art
Transformers are extensively used in electrical and electronic appliances. Transformers function to step voltages up or down, to couple signal energy from one stage to another, or for impedance matching. Transformers may also be used in magnetic circuits with solenoids and motor stators.
Transformers typically include a plurality of laminations creating an electrical path around an electric current developed in a winding or other electrical conductor. Conventionally, transformers include two stacks of laminations, one stack which is an E shape and the other stack is an I-shape which closes off the free ends of the E-shaped stack. These E or I-shaped stacks are formed from stacking a given number of properly shaped thin sheets atop one another and secured to one another. Each sheet is typically made from a ferrous material. For example, the sheets forming the stacks of laminations may be riveted together or adhesively assembled using varnish, epoxy resin, or tape, or even held together with spring clips.
Two predominant methods are employed for assembly of the E-shaped stack or laminations to the I-shaped stack of laminations, i.e., either by alternating the core laminations or by welding them together. Welding of the E-I stacks is typically accomplished with expensive machinery operated by highly skilled personnel and consumption of welding products (gas and electrodes). Welding of the stacks of laminations is a relatively expensive undertaking as compared to other methods. Additionally, the welded material interferes with the magnetic performance of the transformer and the welding process causes disruptions in the grain structure of the steel resulting in lower electromagnetic performance.
In order to increase the performance and efficiency of the transformer it is desirable to reduce the gaps of air between adjacent stacks of laminations and/or to increase the contact surface area between the stacks of laminations. Typically, in order to compensate for the gaps of air between the stacks of laminations and to increase the contact surface area between the stacks of laminations, additional sheets of material are added to the stacks of laminations, which, in turn, increase the cost and the size of the transformer.
The need exists for electric transformers, assemblies and the like which are more efficient and less expensive to manufacture as compared to conventional electric transformers.